The Anesthesia Research Center of the University of Washington was established in 1968 as a broad-based multidisciplinary program to investigate problems in anesthesia and related fields. The Center plus affiliated, independently funded programs includes 25 research projects in eight areas: 1) Cellular biochemical mechanisms of anesthesia; 2) respiration; 3) neuropharmacology; 4) obstetric anesthesia and perinatal biology; 5) regional anesthesia; 6) pain; 7) bioengineering and anesthesia; 8) circulation. This proposal is for continuation of three projects plus institution of a new clinical research program. The individual projects are: 1) studies of perceptual distortion in chronic pain. These studies will seek correlation between psychologic pain assessment and physiologic responses to pain in normal individuals and patients with chronic pain, seeking approaches toward more objective diagnosis and quantification of pain states. 2) Investigations of the relationship between pulmonary blood flow and gas exchange will explore in particular the question of the pulmonary blood flow and blood pressure conditions for optimum resolution of pulmonary edema and lung healing. This issue is of great relevance to effective therapy for the adult respiratory distress syndrome, in particular as related to the use of extracorporeal membrane oxygenation. 3) Studies of the effects of anesthesia and anesthetic drugs on the immune response will pursue the concern that anesthesia may modify this defense mechanism so as to put certain persons at increased risk of infection or tumor metastasis during and/or following anesthesia and surgery. The Clinical Research Program is an innovative effort to utilize the extensive resources of the Anesthesia Research Center toward the resolution of clinical problems that lend themselves to studies of relatively short duration (weeks to months) at low cost, addressing questions of direct importance and immediate application to improved patient care.